VERSION: 1.5.1 DOCUMENT CODE: ZELKSM NO. OF PAGES: 8 DAVE s.r.l. www.dave.eu Zefeer Embedded Linux Kit Software Manual
2 Printed in Italy Trademarks Ethernet is a registered trademark of XEROX Corporation All other trademarks are the property of their respective owners Copyright All rights reserved. Specifications may change any time without notification. Company Address DAVE S.r.L. Via Forniz 2 33080 Porcia (PN) Italy Phone: +39 0434 921215 e-mail: info@dave.eu URL: www.dave.eu Technical Support (available to registered kit owners only) e-mail: support-zefeer@dave.eu
3 History Version Date Notes 0.9.0 December 2004 first draft 0.9.5 March 2005 added ZELKH support including a.n. about Microwindows and IDE hard disk 1.0.0 October 2005 Fixed memory map Moved to new default boot configuration. Small corrections. Added details about LCD connection. 1.0.1 November 2005 Small corrections. 1.1.0 November 2005 Removed application note about Microwindows; this has been moved to AN-PI-001. Changed section about SerialFlasher. Small corrections. 1.5.0 May 2007 Small corrections Added support for modules equipped with P30 and DS1374 Added AN about GPIOs 1.5.1 June 2007 Small corrections Added note about /etc/adjtime
4 Contents 1 - System overview... 9 1.1 Embedded Linux... 9 1.2 Quick start guide... 10 1.3 Memory organization... 11 1.4 Boot process... 13 2 - Developing environment... 24 2.1 Introduction... 24 2.2 The cross compiling environment... 25 2.3 Building U-Boot... 25 2.4 Building Linux kernel... 28 2.5 Customizing the initial ramdisk image... 30 2.6 MTD partitions... 31 2.7 Debugging techniques... 32 3 - Application notes... 33 3.1 How to use the JFFS2 file system... 33 3.2 Setting up the Server environment... 35 3.3 How to use the hardware real-time clock (RTC)... 39 3.4 How to connect LCD panel (ZELKH only)... 40 3.5 How to enable an IDE hard disk (ZELKH only)... 41 3.6 Using GPIOs... 44 3.7 How to use the Maxim DS1374 watchdog timer... 46 4 - FAQs... 49 5 - Notes for ZELK 0.9.x... 50 5.1 U-Boot... 50 5.2 Linux... 50 6 - Bibliography and useful links... 52
5 Introduction Zefeer Embedded Linux Kit: what is? Zefeer Embedded Linux Kit (ZELK for short) provides all the necessary stuff to make the developing environment to: build the U-Boot bootloader build and run Linux operating system on Zefeer/ZefeerEVB systems build Linux applications that will run on the target. There are two versions available: Zefeer Embedded Linux Kit Low (ZELKL) for ZefeerEVB-L/ZefeerDZB systems Zefeer Embedded Linux Kit High (ZELKH) for ZefeerEVB-H/ZefeerDZQ systems
6 The kit is composed by: 1. ZefeerEVB/Zefeer system with the term ZefeerEVB we refer to the host board the Zefeer processor module is plugged onto. Two ZefeerEVB boards are available: ZefeerEVB-L and ZefeerEVB-H. The kits come in two different configurations as shown in table 1. For a comprehensive list of available modules, please see reference [1]. Kit name Host board Processor module ZELKL ZefeerEVB-L ZefeerDZB ZELKH ZefeerEVB-H ZefeerDZQ Tab. 1 - Kit configurations 2. U-Boot bootloader sources 3. Linux kernel 2.6 sources 4. cross tool chain for x86 host this is based on GCC 4.0.0 and it is part of the Embedded Linux Development Kit (ELDK) for ARM version 4.1 by Denx Software Engineering (see also reference [2]) 5. root file system mounted by the target via NFS this item is part of the Embedded Linux Development Kit (ELDK) for ARM version 4.1 by Denx Software Engineering (see also reference [2]) 6. small root file system (ext2) mounted as ramdisk this item is part of the Embedded Linux Development Kit (ELDK) for ARM version 4.1 by Denx Software Engineering (see also reference [2]) 7. technical documentation hardware manuals, mechanical drawings, schematics, software manuals and application notes. The documentation related to the software helps the user to quickly start and configure the bootloader and the operating system. For more details about technical characteristics of processor modules, please see reference [3]. For more details about technical characteristics of evaluation boards, please see references [4] and [5]. All the files (sources, documentation etc.) may or may not be delivered on physical media (CDROM or USB memory stick) depending on the purchase order code. However they are always available on-line on our web site. Access to these files is granted to registered kit owner's only.
7 Zefeer Embedded Linux Kit: what is not? The kit is not a complete Linux programming guide nor a Linux Reference Guide. Internet provides tons of information, tutorials and examples about writing applications and drivers for this operating system and how to work with it from the user's point of view (just try to type Linux programming in your favourite search engine for example). As the kit is heavily based on open-source community-maintained software projects, ZELK does not provide exhaustive documentation for these software items but it points out where to find the information on the Internet or books. For example, for the U-Boot bootloader, the kit does not list all the commands it handles but provides the link to the on-line documentation and to the public mailing list used by its users. About this manual This document describes how to run Linux on the ZefeerEVB/Zefeer system 1. For novice users who have no experience at all about embedded Linux systems, reading of reference [6] is strongly recommended. Pratically speaking, that book covers all the matters involved in developing software for such systems (from tool chain organization to the most famous file systems running on top of MTD). It is not a reference guide, but it provides a complete and exhaustive overview that makes the developer to save a lot of time in searching such information over the Internet. If you need a briefer but exhaustive overview of the Linux and Embedded Linux world, please have a look at the training section of reference [7]. Since Zefeer Embedded Linux Kit makes use of some parts of the Embedded Linux Development Kit (ELDK) for ARM version 4.1 by Denx Software Engineering, we will often refer to The Denx U-Boot and Linux Guide (DULG), reference [8]. The latest version is freely available here: http://www.denx.de/twiki/bin/view/dulg/manual. The default kit configuration will have the following software modules stored in Flash (more details can be found in the paragraph ): U-Boot boot loader Linux kernel compressed image (2.6.x) initial ramdisk compressed image containing a typical set of applications suited for embedded systems. The hardware (ZefeerEVB/Zefeer processor module) is ready to start. It means you have just to connect a PC s COM port to the board s serial port with a null-modem cable and you can access the U-Boot bootloader shell (see also clause on page ). 1 The document covers both the ZELKL and ZELKH kits.
8 Support service and software upgrades Technical support is delivered through email exclusively. Only registered kits owners can access the support service. The address is support-zefeer@dave.eu. Software upgrades are available for download in the restricted download area of DAVE web site www.dave.eu. Registration is required to access this area. To do that, please follow the instructions in the Download area of our web site. The two required serial numbers are printed close to the bar codes, one on the processor module and one on the evaluation board. For both services, coverage is lifetime for processor module buyers and one year for the other customers.